QU-BD OneUp/TwoUp Pulley for Gantry Counterweight

I modified lwilder's Parametric Pulley Assembly (http://www.thingiverse.com/thing:571542) scad file to allow you to change the radius of the pulley, added a guide to help keep the rope in place, and modified the dimensions of the mount.

What I use it for is supporting the gantry with a counterweight. Just attach the pulley to the top with double sided tape and string it up. The current size of the pulley is sufficient for allowing a rope to go over the top without rubbing against anything